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ARM7: Extend prefetch by one stage

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@endrift
endrift committed Dec 20, 2014
1 parent f57b47b commit 28ac288d2cc753aab0493a471726cc5795a09363
Unified Split
Showing with 26 additions and 19 deletions.
  1. +1 −0 CHANGES
  2. +6 −4 src/arm/arm.c
  3. +1 −1 src/arm/arm.h
  4. +4 −2 src/arm/isa-inlines.h
  5. +8 −8 src/gba/gba-memory.c
  6. +4 −2 src/gba/gba-serialize.c
  7. +2 −2 src/gba/gba.c
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1 CHANGES
@@ -10,6 +10,7 @@ Bugfixes:
- GBA BIOS: Fix HLE Lz77 and RL functions to properly account for width and invalid addresses
- ARM7: Fix LDM writeback to a register already written
- GBA Memory: Don't call into GPIO write calls if GPIO devices are absent
+ - ARM7: Extend prefetch by one stage
Misc:
- Qt: Disable sync to video by default
- GBA: Exit cleanly on FATAL if the port supports it
View
10 src/arm/arm.c
@@ -176,9 +176,10 @@ void ARMRaiseSWI(struct ARMCore* cpu) {
}
static inline void ARMStep(struct ARMCore* cpu) {
- uint32_t opcode = cpu->prefetch;
- LOAD_32(cpu->prefetch, cpu->gprs[ARM_PC] & cpu->memory.activeMask, cpu->memory.activeRegion);
+ uint32_t opcode = cpu->prefetch[0];
+ cpu->prefetch[0] = cpu->prefetch[1];
cpu->gprs[ARM_PC] += WORD_SIZE_ARM;
+ LOAD_32(cpu->prefetch[1], cpu->gprs[ARM_PC] & cpu->memory.activeMask, cpu->memory.activeRegion);
unsigned condition = opcode >> 28;
if (condition != 0xE) {
@@ -239,9 +240,10 @@ static inline void ARMStep(struct ARMCore* cpu) {
}
static inline void ThumbStep(struct ARMCore* cpu) {
- uint32_t opcode = cpu->prefetch;
- LOAD_16(cpu->prefetch, cpu->gprs[ARM_PC] & cpu->memory.activeMask, cpu->memory.activeRegion);
+ uint32_t opcode = cpu->prefetch[0];
+ cpu->prefetch[0] = cpu->prefetch[1];
cpu->gprs[ARM_PC] += WORD_SIZE_THUMB;
+ LOAD_16(cpu->prefetch[1], cpu->gprs[ARM_PC] & cpu->memory.activeMask, cpu->memory.activeRegion);
ThumbInstruction instruction = _thumbTable[opcode >> 6];
instruction(cpu, opcode);
}
View
2 src/arm/arm.h
@@ -149,7 +149,7 @@ struct ARMCore {
int32_t shifterOperand;
int32_t shifterCarryOut;
- uint32_t prefetch;
+ uint32_t prefetch[2];
enum ExecutionMode executionMode;
enum PrivilegeMode privilegeMode;
View
6 src/arm/isa-inlines.h
@@ -52,15 +52,17 @@
#define ARM_WRITE_PC \
cpu->gprs[ARM_PC] = (cpu->gprs[ARM_PC] & -WORD_SIZE_ARM); \
cpu->memory.setActiveRegion(cpu, cpu->gprs[ARM_PC]); \
- LOAD_32(cpu->prefetch, cpu->gprs[ARM_PC] & cpu->memory.activeMask, cpu->memory.activeRegion); \
+ LOAD_32(cpu->prefetch[0], cpu->gprs[ARM_PC] & cpu->memory.activeMask, cpu->memory.activeRegion); \
cpu->gprs[ARM_PC] += WORD_SIZE_ARM; \
+ LOAD_32(cpu->prefetch[1], cpu->gprs[ARM_PC] & cpu->memory.activeMask, cpu->memory.activeRegion); \
currentCycles += 2 + cpu->memory.activeUncachedCycles32 + cpu->memory.activeSeqCycles32;
#define THUMB_WRITE_PC \
cpu->gprs[ARM_PC] = (cpu->gprs[ARM_PC] & -WORD_SIZE_THUMB); \
cpu->memory.setActiveRegion(cpu, cpu->gprs[ARM_PC]); \
- LOAD_16(cpu->prefetch, cpu->gprs[ARM_PC] & cpu->memory.activeMask, cpu->memory.activeRegion); \
+ LOAD_16(cpu->prefetch[0], cpu->gprs[ARM_PC] & cpu->memory.activeMask, cpu->memory.activeRegion); \
cpu->gprs[ARM_PC] += WORD_SIZE_THUMB; \
+ LOAD_16(cpu->prefetch[1], cpu->gprs[ARM_PC] & cpu->memory.activeMask, cpu->memory.activeRegion); \
currentCycles += 2 + cpu->memory.activeUncachedCycles16 + cpu->memory.activeSeqCycles16;
static inline int _ARMModeHasSPSR(enum PrivilegeMode mode) {
View
16 src/gba/gba-memory.c
@@ -14,7 +14,7 @@
#include "util/memory.h"
static uint32_t _popcount32(unsigned bits);
-static uint32_t _deadbeef = 0xDEADBEEF;
+static uint32_t _deadbeef[2] = { 0xDEADBEEF, 0xFEEDFACE };
static void GBASetActiveRegion(struct ARMCore* cpu, uint32_t region);
static void GBAMemoryServiceDMA(struct GBA* gba, int number, struct GBADMA* info);
@@ -128,7 +128,7 @@ static void GBASetActiveRegion(struct ARMCore* cpu, uint32_t address) {
return;
}
if (memory->activeRegion == REGION_BIOS) {
- memory->biosPrefetch = cpu->prefetch;
+ memory->biosPrefetch = cpu->prefetch[0];
}
memory->activeRegion = newRegion;
switch (address & ~OFFSET_MASK) {
@@ -158,7 +158,7 @@ static void GBASetActiveRegion(struct ARMCore* cpu, uint32_t address) {
cpu->memory.activeMask = SIZE_CART0 - 1;
break;
default:
- cpu->memory.activeRegion = &_deadbeef;
+ cpu->memory.activeRegion = _deadbeef;
cpu->memory.activeMask = 0;
GBALog(gba, GBA_LOG_FATAL, "Jumped to invalid address");
break;
@@ -176,7 +176,7 @@ static void GBASetActiveRegion(struct ARMCore* cpu, uint32_t address) {
if (cpu->cycles >= cpu->nextEvent) { \
value = gba->bus; \
} else { \
- value = cpu->prefetch; \
+ value = cpu->prefetch[0]; \
if (cpu->executionMode == MODE_THUMB) { \
value |= value << 16; \
} \
@@ -303,7 +303,7 @@ int16_t GBALoad16(struct ARMCore* cpu, uint32_t address, int* cycleCounter) {
if (cpu->cycles >= cpu->nextEvent) {
value = gba->bus;
} else {
- value = cpu->prefetch;
+ value = cpu->prefetch[0];
}
}
break;
@@ -359,7 +359,7 @@ int16_t GBALoad16(struct ARMCore* cpu, uint32_t address, int* cycleCounter) {
if (cpu->cycles >= cpu->nextEvent) {
value = gba->bus;
} else {
- value = cpu->prefetch;
+ value = cpu->prefetch[0];
}
break;
}
@@ -396,7 +396,7 @@ int8_t GBALoad8(struct ARMCore* cpu, uint32_t address, int* cycleCounter) {
if (cpu->cycles >= cpu->nextEvent) {
value = gba->bus;
} else {
- value = cpu->prefetch;
+ value = cpu->prefetch[0];
}
}
break;
@@ -454,7 +454,7 @@ int8_t GBALoad8(struct ARMCore* cpu, uint32_t address, int* cycleCounter) {
if (cpu->cycles >= cpu->nextEvent) {
value = gba->bus;
} else {
- value = cpu->prefetch;
+ value = cpu->prefetch[0];
}
break;
}
View
6 src/gba/gba-serialize.c
@@ -82,10 +82,12 @@ void GBADeserialize(struct GBA* gba, struct GBASerializedState* state) {
gba->cpu->memory.setActiveRegion(gba->cpu, gba->cpu->gprs[ARM_PC]);
if (gba->cpu->cpsr.t) {
gba->cpu->executionMode = MODE_THUMB;
- LOAD_16(gba->cpu->prefetch, (gba->cpu->gprs[ARM_PC] - WORD_SIZE_THUMB) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
+ LOAD_16(gba->cpu->prefetch[0], (gba->cpu->gprs[ARM_PC] - WORD_SIZE_THUMB) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
+ LOAD_16(gba->cpu->prefetch[1], (gba->cpu->gprs[ARM_PC]) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
} else {
gba->cpu->executionMode = MODE_ARM;
- LOAD_32(gba->cpu->prefetch, (gba->cpu->gprs[ARM_PC] - WORD_SIZE_ARM) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
+ LOAD_32(gba->cpu->prefetch[0], (gba->cpu->gprs[ARM_PC] - WORD_SIZE_ARM) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
+ LOAD_32(gba->cpu->prefetch[1], (gba->cpu->gprs[ARM_PC]) & gba->cpu->memory.activeMask, gba->cpu->memory.activeRegion);
}
GBAMemoryDeserialize(&gba->memory, state);
View
4 src/gba/gba.c
@@ -227,9 +227,9 @@ static void GBAProcessEvents(struct ARMCore* cpu) {
int32_t nextEvent = INT_MAX;
int32_t testEvent;
- gba->bus = cpu->prefetch;
+ gba->bus = cpu->prefetch[0];
if (cpu->executionMode == MODE_THUMB) {
- gba->bus |= cpu->prefetch << 16;
+ gba->bus |= cpu->prefetch[0] << 16;
}
if (gba->springIRQ) {

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